DARRINGTON, Wash. — A contractor who studied the risks to a rural neighborhood in Washington state wiped out by a mudslide last month made recommendations more than a decade ago that included possible relocation of homes elsewhere.
News of the recommendations, made in a report for a Native American tribe with traditional fishing rights in the area, emerged as searchers scoured a pile of mud and debris for victims of the March 22 slide that left dozens dead or missing.
About 30 people have been confirmed dead from the slide, which roared over the north fork of the Stillaguamish River and state Highway 530, engulfing about three dozen homes on the outskirts of the rural town of Oso in the foothills of the Cascade Mountains. Another 17 remain listed as missing.
Jim Miller, a geological engineer with GeoEngineers, said his company prepared a 2001 report for the Stillaguamish tribe that warned of a “significant risk to human lives and private property” at the slide site.
The report, commissioned to assess the impact of landslides on salmon, proposed that the river be diverted to the south, away from the slide site and onto private property that would have to be acquired.
It offered three options, from diverting the river 500 feet — which would not have affected residential areas — to moving it 2,000 feet, which would have covered the entire neighborhood and required the removal of homes.
“We recommended any of those three options, the most extensive being the most protective,” Miller said.
The report found the most feasible option would be the 500-foot diversion, which included shoring up the hillside, since residents were likely to object to being relocated, he added.
The report did not anticipate the full scale of the slide, however, Miller said. “This was a much larger event than was predicted by anybody, including us,” he added.
The study was cited in a 2004 Snohomish County flood management plan, in which the county resolved to reinforce the unstable hillside, part of which later tumbled in a 2006 slide.
Rebecca Hoover, spokeswoman for the Snohomish County Executive’s office, declined to discuss the issue, saying it was not the appropriate time, as efforts focused on searching for victims and supporting grieving families.
Those living in the devastated neighborhood were not aware how much of a danger the hillside posed, said Ruth Hargrave, 67, whose vacation home was destroyed by the slide.
“It’s impossible to believe we all knew it but we’d take our chances,” she said.
County property records show seven more houses were built in the path of the slide on Steelhead Drive in 2005 and 2006. Several of their residents, including children, are among the dead and missing.
No one has been pulled alive from the rubble since the day of the landslide, when at least eight people were injured but survived, and rescue teams have since found no signs of life.